Best panel choice for 6 panel string to match inverter MPPT range and efficiency

[SeaGal]

Am looking at 2 panels options to connect to a Solis EH1P 6kW inverter. The inverter has 2 MPPT inputs with 120V start-up, MPPT voltage range of 90-520V and Max. input current 15 A.

One of the strings will only have 6 panels in it.

Am considering two different makes of panels (each 430Wp):-
One (Trina) has max power at 42.3V & 10.17A.
The other (Longi) has max power at 32.84V & 13.10A.

Would there be, in real-life usage, any reason to choose one panel over the other?

The higher voltage panels will generate a voltage that sits further up the inverter's MPPT range and my gut feeling is that would result in better performance. Or, is the "performance" of an MPPT tracker so good it works just as well at any voltage? Also, I am wondering whether a higher PV voltage would result in better efficiencies in converting PV input to the internal DC bus?

Obviously there will be less DC loss at 10A, rather than 13A, but the distance between panels and inverters is going to be quite short.

 

[Mattb4]

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Would there be, in real-life usage, any reason to choose one panel over the other?

...

Cost. Also size (L X W) can affect method of mounting or suitability for a particular layout. Other than that I doubt you would see any difference in output from you SCC.

Of course there is also esthetics. If one is all black it might not match you color scheme though every woman needs a little black solar panel.

 

[Hedges]

If known, whatever MPPT operating point of panels gives highest efficiency for SCC.
The difference in harvested power will be small, but difference in power dissipated inside SCC, therefore temperature rise, could be 1.5x or 2x.

Also, consider NOCT or PTC specs of panels. Although same STC, actual yield could differ. Maybe also low light performance. And temperature performance; that is on data sheet.

 

[SeaGal]

If known, whatever MPPT operating point of panels gives highest efficiency for SCC.

So, the Solis spec sheet shows these entries...
Max. input voltage 600 V
Rated voltage 330 V
Start-up voltage 120 V
MPPT voltage range 90-520 V
Max. input current 15 A / 15 A

Do you think the 'rated voltage' means the point of highest efficiency or something else - trying to learn chinglish here!

Also, consider NOCT or PTC specs of panels. Although same STC, actual yield could differ. Maybe also low light performance. And temperature performance; that is on data sheet.

 

[Hedges]

Rated voltage should at least be a voltage where it can process specified watts.
e.g. some SMA battery inverters have 30A max input, 100V to 500V operation, 6000W rating. Can function at 100V but can't deliver full wattage.
I suspect may not reach utility AC voltage high tolerance at lowest operating voltage, if input outside nominal spec range.

For yours, 90V x 15A x 2 = 2700W. Not quite 6kW.

String of 6x using one panel would be 253.8Vmp, other 197V.
More than 2x minimum voltage, plenty for high temperature and partial shading.

Don't suppose they give efficiency vs. voltage curves? Probably more efficient closer to rated 330V.

 

[SeaGal]

Don't suppose they give efficiency vs. voltage curves?

I haven't seen them for the Solis. If anyone has seen them it will be @Solar Guppy I guess (unsubtle tag there )